Post-irradiation effects on the chemical structure of the ion-beam irradiated isotactic-polypropylene

Oka, Toshitaka   ; Oshima, Akihiro*; Kudo, Hisaaki*; Murakami, Takeshi*; Washio, Masakazu*; Hama, Yoshimasa*

Post-irradiation effects of isotactic-polypropylene induced by various ion-beams in vacuum at room temperature are investigated. The chemical structure of the samples were characterized by a micro-FT-IR spectrometer and an UV-Vis spectrometer. From the results, LET effects on the formation of the chemical structures corresponding to the absorption of the CH rocking/C-C stretching at 973 cm was observed. The formation of carbonyl group at 1716 cm is dominant near the surface, the absorption of carbonyl group decreases with increasing depth from the surface. During the long-time storage, the carbonyl group increases regardless of the depth from the surface. It suggests that the long-term oxidation of the polypropylene due to the irradiation, especially near the Bragg peak, continues more than one year.